text: /* 7600
   * ^[a-z]+([a-z0-9-]*[a-z0-9]+)?(\.([a-z]+([a-z0-9-]*[a-z0-9]+)?)+)*$
   * EXPONENT
   * nums:3
   * EXPONENT AttackString:"a."+"aa"*8+"!1 __EOA(i or ii)"
   */
  var REGEX = /^[a-z]+([a-z0-9-]*[a-z0-9]+)?(\.([a-z]+([a-z0-9-]*[a-z0-9]+)?)+)*$/
  for(var i = 1; i <= 5000000; i++) {
      var time = Date.now();
      var attack_str = 'a.' + 'aa'.repeat(i*1) + '!1 __EOA(i or ii)'
      REGEX.exec(attack_str)
      // REGEX.test(attack_str);
      // attack_str.search(REGEX)
      // attack_str.match(REGEX)
      var time_cost = Date.now() - time;
      console.log(i * 1 + ": " + time_cost+" ms")
  }